[The value of sinonasal CT scan in diagnosing of eosinophilic chronic rhinosinusitis with nasal polyps].

Objective: To compare the value of sinonasal CT scan with other clinical parameters in the pre-diagnosis of eosinophilic chronic rhinosinusitis with nasal polyps (eCRSwNP). Methods: From January to May of 2016, One hundred and fifty consecutive CRSwNP patients (90 eCRSwNP and 60 non-eosinophilic CRSwNP) undergoing endoscopic functional sinus surgery in Beijing Tongren Hospital were recruited in this study. Preoperative CT scan, skin prick test (SPT) and oral fractional exhaled nitric oxide (FeNO) measurements were performed in each patient and full blood count with differential analysis was performed within 1 week before surgery. t test and X2 test were used to compare the age, gender, history of surgery, onset of asthma, history of allergy, CT scores' ratio for the ethmoid sinus and maxillary sinus (E/M ratio) and presence of osteoneogenesis of two groups. Mann-Whitney analysis was used to compare the total Lund-Mackay scores, FeNO and blood eosinophil counts of two groups. Logistic regression analysis and receiver operating characteristic (ROC) curve were used to assess the predictive value of clinical parameters. Results: E/M ratio, FeNO, blood eosinophil percentage of eCRSwNP group was significantly higher than those of non-eosinophilic CRSwNP group [3.56±0.37 vs 1.80±0.10, (34.4±18.1) μg/L vs (22.1±11.7) μg/L, 8.19%±1.50% vs 4.55%±5.60%; χ(2) value was 0.900; t value was 0.994 and 0.900, respectively; all P<0.05]. E/M ratio had the highest predictive value, with area under curve (AUC) value of 0.938. The cut-off point of 2.59 for E/M ratio demonstrated a sensitivity of 94.3% and a specificity of 89.6% for eCRSwNP. Conclusion: The E/M ratio is a more useful predictor in the diagnosis of eCRSwNP compared to other clinical parameters.